1. Field of the Invention
The present invention relates to a semiconductor package pickup apparatus. More particularly, the present invention relates to a semiconductor package pickup apparatus, which picks up individual semiconductor packages in order to transfer the semiconductor packages or loads the semiconductor packages onto a package stacker.
2. Related Prior Art
In general, a semiconductor manufacturing process is mainly divided into a fabrication process and an assembly process. During the fabrication process, integrated circuits are designed on a silicon wafer so as to form a semiconductor chip. In addition, during the assembly process, a semiconductor strip is fabricated by sequentially performing various steps of attaching the semiconductor chip to a lead frame, electrically connecting the semiconductor chip to the lead frame using wires (or solder balls), and molding the semiconductor chip with resin, such as epoxy. Such a semiconductor strip is mounted on a chuck table by means of a strip picker and then transferred to a sawing device, so that the sawing device saws the semiconductor strip into individual packages by using a cutting blade (rotating blade). The individual packages are stacked onto a package stacker after they are washed and dried, and then transferred to a vision inspection device.
Meanwhile, after the drying process has been completed, the semiconductor packages are stacked on first and second stack sections 510 and 520 of the package stacker 500 as shown in FIG. 4. If margin cavities 510b and 520b and stack recesses 510a and 520a are alternately aligned in the first and second stack sections 510 and 520 in order to precisely load the semiconductor packages on the first and second stack sections 510 and 520, the package pickup apparatus simultaneously picks up the semiconductor packages from a drying device 400 and then sequentially loads the semiconductor packages half-and-half onto the first and second stack sections 510 and 520 of the package stacker 500. Such a package stacker 500 is disclosed in Korean Patent Registration No. 0396982, which has been issued to applicant of the present invention, so detailed description for the package stacker will be omitted.
FIGS. 1 to 3 show the conventional package pickup apparatus.
As shown in FIGS. 1 to 3, the conventional package pickup apparatus includes a picker base 100, a pad holder 200 and an adsorption pad 300.
The picker base 100 is formed at an inner portion thereof with first and second main feeding holes 120a and 120b connected to first and second pneumatic lines 110a and 110b, which provide pneumatic pressure. In addition, the picker base 100 is formed at a bottom surface thereof with first and second gull-shaped distribution grooves 140a and 140b, which are alternately aligned corresponding to the stack recesses 510a and 520a formed in the package stacker 500. The picker base 100 is formed at an inner portion thereof with a first transfer hole 130a, which connects the first main feeding hole 120a with the first distribution groove 140a, and a second transfer hole 130b, which connects the second main feeding hole 120b with the second distribution groove 140b. The pad holder 200 is fixed to the bottom surface of the picker base 100 in order to support the adsorption pad 300. The adsorption pad 300 is formed at a bottom surface thereof with a plurality of adsorption holes 310a and 310b so as to directly absorb the semiconductor packages. In general, the adsorption pad 300 is made from rubber or sponge in order to protect the semiconductor package while enhancing the adsorption force relative to the semiconductor packages.
FIGS. 5 to 8 are sectional views, which are taken along line C-C of FIG. 1 in order to illustrate the operational state of the semiconductor package pickup apparatus.
As shown in FIGS. 5 to 8, the conventional semiconductor package pickup apparatus is controlled in such a manner that pneumatic pressure can be independently fed into adsorption holes 310a and 310b, which are aligned corresponding to the stack recesses 510a and 520a of the first and second stack sections 510 and 520 provided in the package stacker 500, in order to sequentially load the semiconductor packages half-and-half onto the first and second stack sections 510 and 520 of the package stacker 500. That is, when the semiconductor package pickup apparatus picks up the semiconductor packages stacked on the drying device 400, as shown in FIG. 5, vacuum pressure is fed into the first and second main feeding holes 120a and 120b, so that the semiconductor package pickup apparatus can pick up the semiconductor packages. In addition, when the semiconductor package pickup apparatus loads the semiconductor packages onto the first or second stack section 510 or 420 of the package stacker 500, as shown in FIG. 8, pneumatic pressure is fed into the first main feeding hole 120a (or second main feeding hole 120b) so that the semiconductor packages are separated from the semiconductor package pickup apparatus.